The present invention relates to coil winders, and particularly those designed to produce coils for use in the electric and/or electronic field.
As is known, there are a wide variety of coil winders which comprise, on the one hand, coil winders with revolving turret and, on the other hand, coil winders in line. In the coil winders with revolving turret--of which an example is provided in the West German Pat. No. 2,322,064 in the name of the same Applicant--the coils are mounted on spindles radially projecting from a rotary indexing turret, so that the single coils are moved forward through successive working stations, for instance at least one loading station, a winding station and an unloading station, in addition to one or more supplementary or finishing working stations; thus, when the coils are unloaded, they are substantially finished and ready for use. Another type of turret coil winder, designed to produce coils with few turns, having very special functions, is described for example in the EP-A No. 2-120168 in the name of GRUMMAN AEROSPACE CORP.
In the coil winders in line--which also include the machine according to the present invention--the coils are instead carried by a plurality of spindles with parallel axes, which are mounted for rotation on a single support bed or crosspiece, with their axis transverse to that of the spindles. These coil winders merely provide to load, wind and unload the coils; any supplementary or finishing operations on the coils are not carried out on the coil winder in line, but on other machines positioned downstream thereof.
Coil winders of this type are widely known, especially for producing coils with fairly simple winding and with a large number of turns, at high production rates. In these machines, the support spindles have a simple, high-speed rotary motion, a wireguide cooperating with each spindle to distribute the wire on the coil winding, said wireguide having a main back and forth motion along the spindle axis. Preferably, such wireguides are also adapted to perform a more complex motion--usually under numerical control--in order to twist the winding ends on the coil terminals.
In the more modern coil winders, the bed supporting the spindles is rotatable about a horizontal, longitudinal axis of the machine, in order to take up two working positions rotated by 180.degree. one in respect of the other, and the two opposite surfaces of the bed carry two respective sets of spindles, with axes perpendicular to that of the bed, each spindle of one set being coaxial with but independent from a spindle of the opposite set. This arrangement allows carrying out the winding on a plurality of spindles--called hereinafter a first set of spindles--facing the inner part of the machine, where the wireguides operate, while the unloading of the finished coils and the loading of the single empty coil supports can be carried out on another plurality of spindles--called hereinafter a second set of spindles--facing outwardly towards the operator.
The advantage of such an arrangement is obvious, as it allows eliminating the dead times of the loading and unloading operations: in fact, at the end of the winding of a plurality of coils, the bed is tilted by 180.degree.--obviously, in a very short lapse of time, which is practically neglectable as compared to the time required for winding the coils--and the winding of another plurality of coils is started at once, while the unloading and loading operations are carried out on the front of the machine.
In most of the known coil winders in line, each set of spindles is controlled in a substantially independent manner, so that the rotation of the spindles of the first set by no means affects the rotation of the spindles of the second set, and these latter can be held stationary for the loading and unloading operations, while the first ones rotate to carry out the winding.
According to a first known arrangement, the motion transmission controlling the rotation of the first set of spindles, namely those facing the inside of the machine, comprises a plurality of driving shafts, carried by the stationary part of the machine, each shaft having an end adapted to engage with the end of a corresponding spindle--for example by a groove-and-tongue joint--in order to drag it directly into rotation. In this manner, the spindles of the second set, namely those facing the operator, are necessarily disengaged from said driving shafts.
According to a further known arrangement, the spindles of a first set are mutually interconnected by a motion transmission housed inside the bed or crosspiece; a second motion transmission--totally independent from the first--moreover mutually connects the spindles of the second set. Each of the two motion transmissions is connected to a respective driven shaft, also housed inside the bed. Each of the two driven shafts--independent one from the other in rotation--comprises an end outwardly projecting from the bed and carrying a first clutch portion, for instance a male connector, with which cooperates a second clutch portion, namely a female connector, fixed to the end of the main driving shaft of a motor unit mounted on the stationary part of the machine.
To carry out the winding, said driving shaft is engaged on the driven shaft of the motion transmission of the first set of spindles, to cause the rotation thereof, while the driven shaft of the second set of spindles is obviously disengaged from said driving shaft and the corresponding spindles are positioned for the loading and unloading operations.